To date, no clinical pharmacotherapy is available that can totally reverse cocaine addiction. It is partly because the molecular basis of cocaine addiction has not yet been fully elucidated. However, recent studies have implicated that addiction drugs induce early transmitter release (dopamine, glutamate, etc) and activate the postsynaptic receptors which initially mediate the activation of numerous intracellular signaling cascades that alter gene expression, and eventually induce changes in growth factors, cytoskeletal and adhesion molecules, and many other proteins needed to form new synapses, morphologically resulting in increases of spine number and dendritic branching in the cells in prefrontal cortex (PFC) and nucleus accumbens (NAc). Our studies demonstrated that cocaine sensitization is associated with BDNF-ILK-Akt signaling activation and GluR1 phosphorylation in PFC and NAc core. Pergolide/ondansetron given in the chronic cocaine withdrawal period reverses the behavioral sensitization accompanied with the reversal of BDNF-ILK-Akt activation and GluR1 phosphorylation. Co-immunoprecipitation demonstrated that ILK physically interacts with both Akt and GluRl. In this proposal, we will utilize the novel RNA interference (RNAi) approach, recombinant adeno-associated virus, and Tet-On regulation system to establish a sustained, conditional ILK knock down animal model in adult rats. With this model, we will explore the molecular mechanism of ILK associated signaling on chronic cocaine-induced structural and behavioral plasticity, especially investigate whether interference of ILK expression in PFC and NAc core will result in the reversal in changes in GluRl subunits phosphorylation, AMPA receptor trafficking and structural plasticity, subsequently reversing the cocaine-induced sensitization and drug seeking behavior. Success will guide us in elucidating the mechanism of ILK associated signaling in drug addiction and offer instruction for alternative treatments for drug abstinence. [unreadable] [unreadable] [unreadable]